Magnetic space tug and gravitational wave hunters revealed by ESA

21 Jun 2017

Illustration of the chaser magnetic tug. Image: Philippe Ogaki

The next few decades could be exciting for the fields of space research and astronomy as the ESA announces a raft of new spacecraft.

With plans to join China in creating a moon base in the coming decades, the European Space Agency (ESA) is not resting on its laurels when it comes to its next generation of spacecraft.

Its latest reveal came in the form of a trio of laser interferometer space antenna (LISA) spacecraft that will be launched into space to help us better detect gravitational waves being emitted in the universe.

Trio of wave hunters

In 2015, astronomers celebrated the first confirmation of the ripples in spacetime theorised by Albert Einstein over a century ago and, since then, they have been detected a total of three times.

The new LISA mission will be the third large-class mission in ESA’s Science programme, and it has been given the go-ahead after the great success of the initial trial run, the LISA Pathfinder mission.

The three spacecraft will spread in a triangular formation, separated by 2.5m km of space, and will follow Earth in its orbit around the sun.

The Pathfinder mission is expected to conclude its mission at the end of this month and, in the coming years, the ESA will flesh out the mission design and cost, with expectations for a launch in 2034.

Meanwhile, another recent announcement from the ESA revealed a sci-fi-like spacecraft that will hopefully provide a solution to the ongoing problem of space debris in Earth’s orbit.

As Dr Lucy Rogers explained at Inspirefest 2015, the hundreds of satellites we have launched into space over the span of more than half a century are now either out of action or have been destroyed, creating dangerous fragments for active spacecraft and other satellites.

In April, the ESA said it was “very much concerned” by the growing space debris problem, with estimates saying there could be as many as 150m fragments orbiting the Earth at high and lethal speeds for both astronauts and spacecraft.

LISA concept

A concept image of one of the LISA craft. Image: AEI/Milde Marketing/Exozet

Futuristic space tug

That is why the ESA has revealed a potential new weapon in the fight to control the amount of these objects: a giant, futuristic, magnetic space tug.

The spacecraft designed by researcher Emilien Fabacher of the Institut Supérieur de l’Aéronautique et de l’Espace at the University of Toulouse could help overcome the issue of not being able to catch objects tumbling rapidly through space.

“With a satellite you want to de-orbit, it’s much better if you can stay at a safe distance, without needing to come into direct contact and risking damage to both chaser and target satellites,” explained Fabacher.

“So, the idea I’m investigating is: to apply magnetic forces either to attract or repel the target satellite, to shift its orbit or de-orbit it entirely.”

Magnetotorquer

Derelict satellites could, in future, be grappled and removed from key orbits around Earth with a space tug, using magnetic forces. Image: Emilien Fabacher/ISAE-Supaero

If deployed, the space tug would influence target satellites using their ‘magnetorquers’, which are reliable electromagnets already carried to adjust orientation using Earth’s magnetic field without needing any special equipment.

To produce the strong magnetic field to attract the debris, the chaser satellite’s pull would be generated using superconducting wires that are cooled to cryogenic temperatures.

“The first surprise was that it was indeed possible, theoretically. Initially, we couldn’t be sure, but it turns out that the physics works fine,” Fabacher added.

Finally, the ESA also discussed its new planet-hunting spacecraft, PLATO (planetary transits and oscillations of stars), which is going from a blueprint design to actually being constructed.

Following its launch in 2026, PLATO will monitor thousands of bright stars over a large area of the sky, searching for tiny, regular dips in brightness as their planets cross in front of them, temporarily blocking out a small fraction of the starlight.

Colm Gorey was a senior journalist with Silicon Republic

editorial@siliconrepublic.com